SCHEDULE: Castle Biosciences: RTW Investments Reports 9.3% Stake

RTW Investments, LP and Roderick Wong have reported a beneficial ownership of 9.3% in Castle Biosciences, Inc., totaling 2,758,335 shares as of March 31, 2026.

Summary

• RTW Investments, LP, an investment adviser to certain funds, and Roderick Wong, its Managing Partner and Chief Investment Officer, have filed a Schedule 13G amendment.
• They collectively beneficially own 2,758,335 shares of Castle Biosciences, Inc. Common Stock.
• This represents 9.3% of the class of securities outstanding.
• The filing is an amendment to a previous filing, with the event date requiring this statement being March 31, 2026.
• The shares are held by RTW Funds, which have the right to receive dividends and proceeds from sales.

Sentiment

Score: 5

Explanation: StockSavvy.ai views this as a neutral filing, as it primarily reports existing beneficial ownership and does not contain new operational or financial performance data.

Future Outlook

This filing does not contain forward-looking statements or guidance regarding future performance.

Industry Context

StockSavvy.ai notes that this Schedule 13G filing indicates a significant institutional investor, RTW Investments, LP, has taken a notable stake in Castle Biosciences, Inc. Such filings are common for investment firms managing pooled capital and signal a level of active interest in the company's performance and strategy.

Stakeholder Impact

• Shareholders: The filing provides transparency regarding significant institutional ownership, which can influence market perception and trading dynamics.

Key Dates

Keywords

Castle Biosciences, Schedule 13G, RTW Investments, Roderick Wong, Beneficial Ownership, SEC Filing, Investment Adviser, Common Stock